Thermostatic circuit-closer.



J. M. JOHNSON.

THERMOSTATIC CIRGUIT CLUSER.

APPLICATION FILED MAY 1,1912` Patented Oct. 6, 1914.

JGI-IN M. JOHNSON, 0F KANSAS CITY, KANSAS.

THERMOSTATIC CIRCUIT-CLOSER.

Speccaton of Letters Patent.

Patented Oct. 6,1914.

Application led May 1, 1912. Serial No. 694,492.

T0 all whom it may concern Be it known that I, JOHN M. JOHNSON, a citizen of the United States, residin at Kansas City, in the county of Wyangotte and Sta-te of Kansas, has invented certain new and useful Improvements in Thermostatic Circuit-Closers, of which the following is a specification.

My` invention relates to improvements in thermostatic circuit closers, and my object is to provide a novel device of this character which, while susceptible of other uses, is especially adapted for electric lire alarm signals.

Oneofthe features of the invention resides in means whereby the mercurial or other -column within the glass tube of the thermostat may expand to an abnormal degree without breaking said tube. l

Another feature of the invention resides in means for protecting the glass tube and certain terminals communicating therewith, from destruction or deterioration by outside influences.

Other features of the invention will herev inafter appear, and in order that said invenas that disclosed in my tion maybe fully understood, reference will now be made to the accompanying drawing, in which:

Figure 1 is a side elevation of my improved device. Fig. 2 is a central vertical section on line II-II of Fig. 1. Fig. 3 is a plan view of the device. Fig. 4 is an inverted transverse section on line Vv-IV of Fig. 2. Fig. 5 is a vertical central section of the thermostatic tube and certain terminals comf municating with the bore thereof.

In carrying out the invention, I employ a tube 1, consisting, preferably, of glass, or other transparent material, having a bulb 2 at one end and a chamber 3 at its o posite end, which chamber communicates with the bulb through a central longitudinal bore 4, extending through the tube 1.

5 and 6 designate two disconnected terminals of an electric circ t, Such for instance,

p pending application for automatic electric fir alarm system, filed May 1, 1912,'Se`rial Number 694,491, or any other suitable circuit. The lower ends of said terminals 55 and 6 are fused in the lower portion of the tube 1, where they are submerged in mercur orany other uid conductor 7 which wil expand under the ,infiuence of rising temperature. Only a suicient amount Terminals 5, 6 and 8 extend upward along the tube 1, as [shown on Fig. 2, and are connected to conductors 9, 10 and 11, provided, respectively, with depending binding-posts 12, 13 and 14.

-Tube 1 and the terminals communicating therewith are protected from breakage by a cylindrical receptacle 15, provided at its upper end with a circular flange 16, carrying the conductors 9, 10 and 11, and their respective binding-posts. Flange 16 has apertures 17 extending therethrough so that it may be readily secured by bolts or screws to a ceiling, or other suitable. support. Receptacle 15 consists, preferably, of material, which is lire-proof, a good nonconductor, and impervious to water. The inner diameter of receptacle 15 is sufficiently greater than that of tube 1, to leave an annular space, which is filled with material 18 that is both lire and water-proof, to protect the terminals from corrosion, and also to assist receptacle 15A in protecting tube 1, only a portion of the bulb of which is exposed.

`In practice the circuit through the terminals 5 and 6 is normally closed by the fluid conductor 7. Should the device'vbe subjected toatemperature of say 160 degrees, the liquid conductor 7 will expand until the upper terminal 8 is submerged, thereby closing an alarm circuit through terminal 8, the fluid conductor 7 and one of the lower terminals, as set forth in my copending application, above referred to. Should the temperature materially exceed 160 degrees, tube 1 will be prevented from being destroyed by abnormal expansion of the fluid conductor 7 on account of the chamber 3, into which the upper end of the column of fluid flows, thereby relieving said tube lof excessive pressure due to said abnormal expansion.

Should theexposed portion of the bulb 2 become broken and permit the iuid conductor 7 to iow therefrom, the circuit through conductors 5 and 6 will become interrupted and actuate a signal as set forth in my copending application, hereinbefore referred to.

point to which the fluid 7 will expand Having thus described my invention what I claim and desire to secure by Letters Patent, is: 4

1. In combination, a thermostat receptacle comprising a tube, a base flange on the upper end of thetube, a tubular filling of freproof, waterproof material within said tube, and a thermostat mercury tube fitted within said filling, said mercury tubehaving an integral bulb on one end, said bulb being exposed to atmosphere, and electrical vcontacts communicating with the interior of said mercury tube.

` 2. A thermostatic circuit closer, consisting .of a tube having a bulb at one end and a chamber at its'opposite-l end, said chamber communicating 4wi tl1.said bulb through a bore in the tube, a circuit terminal extending into the lower portion of said tube, a circuit terminal extending into the upper i portion of said tube, a fluid conductor in the tube, and a receptacle surrounding saidtube except its bulb, which is exposed to atmosphere,

8. A thermostatic circuit closer, consist- 'ing of a tube having a bulb at one end and a chamber at its opposite end, said chamber communicating with said bulb through al bore in the tube, two disconnected circuit terminals extending into the lower portion of said tube, a iuid conductor in the tube establishing communication between said disconnected terminals, a receptacle surrounding said tube and leaving the bulb exposed to atmosphere, conductors carried by said receptacle to which the terminals are connected, and binding posts communicating with said conductors.

4. A thermostatic circuit closer, consisting of a tube having a bulb at one end and a chamber at its opposite end, said chamber communicating with said bulb through a' bore in the tube, two disconnected circuit terminals extending into the lower portion of said tube, a fluid conductor in the tube tube, a thermostat tubel embedded in said filling but having an integral bulb which is uncovered, and electric connections between the thermostat and said wire-connecting devices.

6. A thermostatic circuit closer, consisting of a tube having a bulb at .one end and a chamber at its opposite end, said chamber communicating with said bulb through .a bore in the tube, two disconnected circuit terminals extending 'into the lower portion of said tube, an upper circuit terminal extending into said tube above the two disconnected terminals, a fluid conductor in the l tube establishing communication` between the two disconnected terminals and adapted -to expand into contact with said upper terminal when subjected to a predetermined temperature, and a receptacle surrounding said tube and adapted to protect same from heat, water, and mechanical breakage, substantially as described.

In testimony whereofl I affix my signature, in the presence of two witnesses.

' JOHN M. JOHNSON. Witnesses:

F. G. FISCHER, E. C. LILLIAN. 

